Railroad sleeper



April 14, 1931. I E N I I i 7 1,800,282

RAILROAD SLEEPER I Filed NOV. 11. 1929 [mi/ Calm.

QM QM Patented Apr. 14, 1931 UNETEE STATES EMIL CAI-IN, OFBERLIN-CHARLOTTENBURG, GERMANY v RAILROAD SLEEPER Application filed.November 11, 1929, Serial No. 406,459, and in Germany February 6, 1928.

The present invention relates to railroad sleepers and more particularlyto hollow sleepers of iron of box cross-section. The invention consistsof a sleeper having a trough-shaped upper member or cover with sidewalls ending at their lower edges in out wardly turned flanges whichengage rigidly in horizontal edges of a lower member which arehook-shaped in cross-section. The lower member consists of a plate domedor of wave shape in the centre, and the side walls of the upper memberslope slightly outwards from the vertical plane so that the hollowsleeper presents a spring effect when the load is I placed upon the topof the upper member.

Both members may be made to the desired section by rolling, and theedges of the lower member may at first be made to stand upwards, andwhen the upper member is placed in position, the edges may be turnedover the flanges of the upper member again by a rolling process.

As a result of the invention, the lower member forms with the uppermember a unitary structure in which no relative movements can occur incontradistinction to the known construction of sleepers where relativemovement gives rise to wear and weakening of the parts forming thejoints between the two members. The novel structure prevents brokenstones and the like from penetrating into the flanges, and therebyprevents the formation of rust, weakening of the joint between themembers, and, as already described, allows a certain resiliency orspringing of the sleeper. The two parts form a unitary sleeper structureof a resistance which remains constant and the spring action alwaysremains the same.

Furthermore, the invention provides a secure support for the sleeper andalso of the track because creeping of the sleeper and breaking up orgrinding of the foundation support cannot occur as does happen instructures in which the upper member can move relatively to the lowermember.

An embodiment of the invention is illustrated in the accompanyingdrawings, where- Figure 1 shows a portion of a rail fixed upon asleeper, the latter being shown in cross-section to an enlarged scale;

Figure 2 is a longitudinal section showing part of the length of thesleeper; while Figures 3 and 4 are longitudinal section and planrespectively, showing the whole length of the sleeper.

The upper member 1 has substantially the shape of the usual railroadtrough sleeper and is provided with horizontal external e0 flanges 2.The lower member 3 is domed or bulged upwardly at the centre and hashorizontal hook-shaped extensions 4. The extensions 4 are first of allmade to extend upwards and are later folded over the flanges 2 of the o5upper member 1. In this way, the upper member 1 and the lower member 3may be formed of two rolled sections. Thetwo members may be joinedtogether by folding over the extensions 4: which may also be effected bya rolling process.

The method of fixing the rails does not form part of the invention. Inthe drawings a method of fixing by means of a weldedon ribbed plate 5,clamping chairs 6, and hammer-headed bolts 7, is shown, illustrating theGerman Reichsbahn construction type K. Instead of this method of fixingthe rails, however, any other suitable construction applicable for ironsleepers may be employed.

In action, the vertical limbs 8 of the upper member tend to springoutwards. They are prevented from doing so more or less by the lowermember 3. They could only spring outwards so far as is allowed by theyielding of the domed or bulged under-member 3. The construction,therefore, affords a spring action which provides a resistance when thelimbs 8 spring apart, and when relieved of load, the limbs 8 return tothe start- 1 ing position.

Owing to the domed or bulged section of the under-member 3 which isconcave on its under surface, this member holds together the foundationmaterial below the sleeper. Thus, the whole of the under surface of thesleeper is continuously afforded a good support. Instead of the undersurface being arc-shaped, it could be given a waved form.

The weight of a sleeper according to the 109 invention amounts to about172 kilograms. This-gives the sleeper a weight of 263.85 kilograms permeter run of the rails. The total weight or" the rails and sleepers inthe case of the German Reichsbahn construction type K amounts forexample, to 381.88 kilograms per meter run, and in the somewhat lighterGermany Government construction type B,

for example, to 376.02 kilograms. Theweight of the sleepers is thusrelatively large in comparison with the total weight.

I claim:

1. A railroad sleeper, comprising a trough shaped upper member havingoutwardly inclmed side walls the lower ends of whlch areoutwardlyextending horizontal flanges,

and an upwardly domed lower memberhaving hcolrshaped edgeswhich rigidlyengage the flanges of said uppermember.

2. A device as in claim 1, in which the domed portion of the lowermember limits the inward retraction of the upper member.

3. A railroad sleeper comprising a trough shaped upper memberhaving-outwardly inclined side walls the lower ends of which areoutwardly extending iorizontal flanges, and an upwardly domed lowermemberex-- tending along the entire length of theupper 7 member andhaving hooked shaped edges which rigidly engage the flanges of the saidupper member, the ends of the upper mem-'- ber being turned downwardlythereby-to obstruct the openings at the ends of said devlce.

In witness whereof I hereunto'subseribe my name this 24 day of October1929."

p EMIL CAI-IN

